In the pharmaceutical industry, a machine for filling capsules with powdery pharmaceutical products is known, comprising a conveyor device which is continuously movable along a given path, and is provided with a number of pockets, each adapted to receive a respective bottom of a corresponding capsule; a rotating container containing the pharmaceutical product; and a dosing wheel mounted to continuously rotate about a longitudinal axis thereof.
The dosing wheel is provided with at least one dosing device, which is moved forward by the dosing wheel firstly through a sampling station where a given amount of product is sampled from the container and then along a portion of the aforesaid path in phase with a corresponding pocket for transferring the product into the corresponding bottom.
The dosing device comprises a cylinder and piston axially movable under the bias of an actuating device comprising, in turn, first and second cams extending about the longitudinal axis of the dosing wheel, a first tappet carried by the cylinder and engaged in the first cam, and a second tappet carried by the piston and engaged in the second cam.
The known machines for filling capsules with pharmaceutical products of the above-described type, although widely tried and tested, have some drawbacks mainly deriving from that the two cams needed to control the axial movements of cylinder and piston should be manufactured with the utmost accuracy and with relatively small tolerances, and are therefore relatively complex and costly.